Gyrocompass transmission system



J. L. CHANTEM ERI-KE vm10 COMPASS TRANSMISSION SYSTEM July 4, 1933.

Filed June 1e, 192s 3 sheets-sheet. 2 Y

NHS TEE7 er/a;

Y. E N R O.

July 4, 1933.

J. L. CHANTEMERLE GYRO COMPASS TRANSMISSION SYSTEM 3 Sheets-Sheet 3Filed June 16, 1926 45' v412 50' 4 fsa INVENTOR n Jaa@ /r /mn wei. v

/TORNEY] Y Patented july 4,A

UNITED STATES JOSEPH L. C HANTEMERLE, F NEW YORK, N. Y., ASSIGNOR, BYMESNE ASSIGNMENTS,v

PATENT OFFICE TO SlERRY GYROSCOPE COMPANY, INC., 0F BRGOKLYN, NEW YORK,CORPORATION OF NEW YORK Application filed June 16,

This invention relates to transmission systems for gyroscopic compasses.It is one object of this invention to provide means whereby both a fineand a coarse indication of the. master compassY reading may betransmitted to the repeater compasses. This construction is applicableto both a D. C. and an A. C. system of transmission and is of greatimportance where a synchronous transmission system is deslred, that 1s,one 1n which the repeater lnstrument cannot get out of step with themaster instrument even though p the master instrument be turned relativeto the repeater when the current is off and later recstablished. Forthis purpose there is usually employed a 1: 1 transmission system, sincein any system of multiplication of movement, that is, where thetransmitter operates a plurality of revolutions for each revolution ofthe master, it is possible forl the repeating instrument to'lose stepwith the master should the master be turned through an angle greaterthan one revolution -instrument through multiplicationgearing so thatthe said fine transmitter operates through a plurality of revolutionsfor each revolution of the master instrument. By causing the finetransmitter to control an auxiliatry repeating instrument, the said.auxiliary instrument acts as a Vernier for the main repeating instrumentand enables fine readings to within, say, 10 minutes of are to be read,while at the same time permitting the system to remain self-synchronous.

It is a further object of my invention to provide a system of fine andcoarse transmission wherein usual compass correctionsmay be introducedinto said transmission system .so that beth the coarse and finetransmitters will transmit corrected readings.

GYROCOMPASS TRANSFISSION SYSTEM Y A 192e. sei-181m. 116,271.

For this vpurpose I may employ means whereby corrections are introducedinto the coarse and line transmitters m the same ratio as saidtransmitters bear to each other.

A. further object of the invention is the transmission system between amaster com-A ass and one or more repeater Compasses. Still furtherobjects and advantages of my invention will become apparent in thefollowing detailed description thereof.

In the accompanying drawings Fig. 1 is a front elevation, partlysectioned vertically and with parts removed, showing provision of an A.C. system of transmission a master gyroscopic compass having myinvention applied thereto.

Fig. 2 is a plan view of the master compass of Fig. 1.

Fig. 3 is a. section taken substantially on the line 3 3 of F ig. 4 anddisclosing a, lostmotion drive between the master compass and atransmitter. A

Fig. 4 is a section taken substantially on the line 4-4 of Fig. 3.

Fig. 5 is an enlarged detailed plan View of the mechanism forintroducing corrections into the transmittters.

Fig. 6 is a vertical section through the coarse transmitter and thecorrecting mechaxliisni taken substantially on the line 6-6 of Fig. 7 isa section taken substantially on the line 7-7 of Fig. 5.

Fig. 8 is an enlarged vertical section through one of the pivot blocksof Fig. 7.

Fig. 9 'is a, Wiring diagram of the transmittels and repeaters.

Referring to Fig. 1 of thc drawings, there will be seen that I haveillustrated my invention as applied to a gy'roscopic compass system,comprising the gyro casing liniwhich operates the gyroscopic rotor, saidcasing being mounted on horizontal axes in the vertical ring 11, saidcasing and ring constituting the sensitive element which is suspendedfrom the spider by any suitable suspension 5 azimuth gear l5 meshingwith a pinion 16 of.

an azimuth motor 17. The mercury ballistic element 18 and eccentricpivot `19 are also disclosed. In accordance with the ordinary method ofoperation of the gyroscopic compass, the azimuth motor causes thefollowfup element 14 to follow the apparent movements of the sensitiveelement and said movements of the follow-up element have heretofore beenindicated by a compass card carried by said follow-up element. Such acard may be provided here but since I illustrate my invention inconnection with a synchronous transmission system wherein thetransmitter has a 1:1 relation with the master compass, may mount thecard C on the armature of the said transmitter T (see Fig. 2).

For synchronous transmission of the movements of the master compass tothe repeaters, I may employ the said transmitter T geared by gearing521-22 to the follow-up element, the said gearing having a 1:1 relation.Although the said transmission system may be a D. C. transmissionsystem, I have illustrate ed my invention in connection with an A. C.transmission system; The transmitter T, therefore, will comprise ieldpoles and an armature, the said armature being rotated by the follow-upelement, md the displacement of the armature relative to the lield polesbeing transmitted to a similar receiver M having similar field poles andarmature to cause said receiving instruments to repeat the movements ofthe transmitter T.' It will be understood that if a l). C. transmissionsystem is employed, said transmission system may be as shown in thepatent to Elmer A. Sperry #1,255,480, dated February 5, 1918, as shownin F ig. (3 thereof, except that the transmitter would have a 1:1relation with the follow-up element instead of rotating a plurality oftim-3s vfor each revolution of theA master compass.

I have shown a compass card C mounted on the shaft of the armature oftransmitter 'l and it will be apparaent that since said card C issub-divided into 360 degrees. as shown in Fig. 2,'accurate readings towithin say 5 or 1() minutes o t are is impossible and at best thereadings can be taken accurately only to within say the nearest degree-At the same time, therefore, that I operate the 1:1 transmitter T, whichI shall hereafter call the coarse transmitter, I operate also a finetransmitterl T having a multiplying gearing connection 16 to the azimuthgear 15, so that said line transmitter TV makes a plurality ofrevolutions, in this case thirtysiX, for each revolution of the mastercompass. A complete revolution of the card C of transmitter T',therefore, corresponds to but 10 of arc and permits reading to within 5or 10 minutes of are. The employment of the fine transmitter T does notdestroy the complete synchronization ofthe transmission system, forshould the master compass be turned through, say, 150 whenthe current isoil', upon reestablishment of the current, repeater motor M will take upa position in exact synchronization with the transmitter T and,therefore, with the master compass, that is, it will be moved throughthe entire 15 while repeater motor M will move through the remaining 5so that the absolute synchronization of the system is at no timedestroyed, and at the same time I am enabled to transmit very tinereadings of the compass movements.

I have further devised a system for intro- Iv ducing the necessarycorrections which must be introduced 1n the repeater instruments andalso preferably in the master compass cards to compensate for variouserrors tlat necessarily arise due to the movements of the ship or otherdirigible craft on which the compass is mounted. The completev theoryunderlying said errors is set forth in the said Sperry patent wherein itis shown that whenever a vessel, on which the compass is mounted, has ameidianal course component, an error is set up which is proportional tothe speed of the ship, the latitude and the course of the ship'. Thetotal error arising from this cause is set forth in the equation aK cosH COS L l tain L in which D is the total correction, a and b areconstants, K is the linear speed of the ship in knots, I-I is theanglein degrees of ships heading or course from the true geographicalnorth, and L is the latitude. From this it will he seen that there aretwo types of corrections to be introduced. tion which is a function ofthe course and must, therefore, be constantly controlled by Y by movingthe field poles which are ordinarily stationary. Thus, as shown in Fig.(i, the field poles may be operated by actuating gears 30, 30 fixed tothe casingr carrying the said poles of the respective transmitters,lsaid gears being controlled by the correcting mechanism in the mannerhereinafter dceov leo r One is a corrccy scribed. Any relative change ofposition between the armature and the field poles will, of course,transmit a change to the receiving instruments, M, M', that is to say,the corrected readings will thus be transmitted to the receivinginstruments. By mountin the lubber ring L for movement with the fie dpoles, as shown in Fig. 6, I introduce the correction by varying theposition of the lubber line as was heretofore done in the said Sperrypatent cited, for instance.

Since the two transmitters T-T are independent of each other, each ofthese must be corrected and the fine transmitter T must havethecorrection multiplied in the same degree as the movement of its dialC is multiplied over that of dial C. Thus,'for example, in theillustration, ca'rd Cmovcs 36 times as rapidly as card C and, therefore,Whatever correction is introduced in transmitter T must be introducedalso in transmitter T and multiplied 36 times. Preferably I employ asingle means for controlling both connections, said means taking theform of a gear 32 at the end of a pivoted segment 33 and said gear beingsuitably geared through idlers and 70 to the pinions 30, 30 fixed tomove with the field poles of the respective transmitters. The ratio ofgearing is such that the correction introduced in the field poles oftransmitter T' is multiplied 36 times with respectto the movement of thefield poles of transmitter T. Not only, therefore, am I enabled by thismeans to transmit both fine and coarse indications, but I am enabled totransmit corrected line and coarse indications.

t will be understood that if ad). C. system of transmission is employed,the same method of introducing the correction may be employed, that. is,a single gear, suitably geared to the armature or trolleys contactingtherewith in the form shown, for instance, in the said Sperry patent,or.in a patent to L. Tanner No. 1,412,760, dated April 11, 1922 forcorrection device for gyroscopic Compasses, to move the' armature andcontacts relatively. As previously stated at least one of said armatureswould have a 1: 1 relationship with the movements ofthe master compass.

It will now be seen fromthe equation set forth hereinbefore that thereare two corrections to be introduced, one of which is an additivequantity which, in any given latitude, may be made in a single operationand the other of which is a continuing correction which is a function ofthe course, being traveled and must, therefore, be at all times tied upwith the compass so th at it may vary as the course varies.

For introducing the first correction, that is, the additive correction,I may merely shift the gear at the end of the segment 33 by any suitableadjusting means like that shown in Fig. 2,A comprising. an adiustingscrew 34 operating in a fixed'bracket 35 and threaded into the gear 32slidably mounted on segment 33. This will at once introduce thecorrection in the two transmitters in the proper ratios and the saidcorrections will be transmitted to the repeating instruments. Thiscorrection is not used in'some types of compasses and may be omittedWhere not needed without-affecting the Voperation of my invention.

For introducing the second correction I may provide means for suitablycontrolling the movements of said segment and its attached gear from themaster compass. For this purpose I may provide upon the followup elementdriven from -tbe master compass a so-called cosine ring 40, that is, aring having either a cam slot, or as shown ar. eccentric roove 41 withina circular member, which is so designed that its eccentricity from pointto point varies in a predetermined degree in accordance with thefunction of the ships heading. The eccentricity of said cosine ringtransmits its movements through a suitable linkage such as the bellcrank 44 and lever 45 to the segment. The connection between said leverand said segment is such that another factor of this correction, namely,the speed and latitude may also be introduced to effect the movement ofthe segment. For this purpose the lever is shown in the form of a forkpivoted within a support'42 at 43 and within said fork slides a pivot 46(shown enlarged in F ig. 8) forming the pivotal connection between thesegment 33 and the lever 45. It will be seen that when the two pivots 43and 4'6 are in alignment, reation of the. lever 45 causes no movement ofthe segment 33. The slidable pivot 46 is moved within grooves 47 bymeans of an adjusting nut 50 mounted on threaded stem 50 which isthreaded through a boss 80 of segment 33 and which is rotatably butnonslida ly mounted at its inner end in the pivotal connection 46. Saidstem also carries a vertical scale 51 graduated in degrees of latitudeand which is readable upon a scale 51 graduated in accordance with speedin knots. The curves on the late 51 are so plotted that when theindicated latitude intersects the curve for the indicated speed, thepivotal connection 46 will be, shifted in accordance with the requiredcombined functions of both speed and latitude. The lever arm between thetwo ivots is thus varied so that any movementof the lever 4 5 will thustransmit a greater or lesser movement to the segmentwhich is ivoted at49 Within support 42. The nal movement of the segment, therefore, is thecomponent of the course as determined by the cosine cam slot 41 and bellcrank 44, and of the speed and latitude, as determined by the positionof the slidable pivot 46.. lhese corrections are introduced into thetransmitters thro-ugh the same gearing 32 as the additive latitudecorrection was introduced so that this correction also is suitablymultiplied in the fine transmitter T.

Since the follow-up element is usually '5 given a continuous smalloscillatory move- -tail in Figs. 3 and 4.

ment, known as the linut, in order to overcome static friction, meansmay be provided herein for eliminating this movement from thetransmitters. For this purpose the gears which are driven by the azimuthgear 22 are not connected directly to the respective armature shafts, asfor example, shaft in Fig. 1, but said gears are connected to saidarmature shaft through a hunt eliminating or lost motion deviceindicated generally at 61. Thus, for example, in Fig. l the gear 21 isconnected to its armature shaft fi() through the hunt eliminating device6l shown in de- Gear 21 is fixed to a shaft 62 which carries a member GSthereon, said member being adapted to engage one or the other of members(34 fixed to a casing 65 which is fixed to thc armature shaft (i0. Themember G3 is of such size and the space'between the members (i4 is suchthat said member 63 engages one or the,I other of said members 64depending upon the direction of rotation of shaft 62 only at a certaindegree of lost motion. This degree of lost mot-ion is equivalent to theamount of movement which would ordinarily be transmitted by the huntingmovement ot the compass and is, therefore, much larger on the fine thanon the coarse transmitter. The degree of lost motion may be varied byany suitable adjusting means which will move members 64 toward or awayfrom member (-33 to reduceithe increasingr space between said member G3and said members (34. For this purpose I have shown in Fig. 3 a pinion67 engaging with the outer threaded periphery 68 of members 64 toefi'ect the necessary adjustment of said members (i4.

In accordance with the. provisions of the patent statutes, I have hereindescribed the principle and operation of my invention, together with theapparatus which I now consider to represent the best embodimentthereof",.but I desire to have it understood that the apparatus shown isonly illustrative and that the invention can be carried out by othermeans. Also, while it is designed to use the various features andelements in the combination and relations described. some of these mayhe altered and others omitted without interfering with the more generalresults outlined, and the invention extends to such use. 1

llaving described my invention, what I claim and desire to secure byLetters Patent is:

l. In combination, a gyroscopic compass, means for transmitting theindications of said compass including coarse and fine transmittershaving a predetermined rat-1o of movement with respect to said compassand to each other, means whereby said compass actuates saidtransmitters, a correction device also actuated from said compass, andmeans for introducing corrections from sai device into each of saidtransmitters in the tions into said transmitters simultaneously in thesame ratio as said first ratio of movement.

3. In combination, a gyroscopic compass adapted to be mounted on acraft, means for transmitting the indications of said compass 7including coarse and lino transmit e C having a predetermined ra A1o omovement with respect to said com-pass and to each other, means wherebysaid compass actuatcs said transmitters, and means for introducingcorrections into said transmitter-gin the same ratio as said first ra ioo movement, comprising a member shifted by movements of the compass,means whereby said member is adjusted to Correct also for speed, andlatitude of said craft and gearing of difiercnt ratios connecting saidmember and each transmitter.

4. In combination, a gyroscopic compass, means fortransmittingindications of said compass including coarse and fine transmittershaving a predetermined ratio of movement with respect to said compassand to cach other, a follow-up element, means whereby said elementactuates said transmitters, and means including a common operatingmember governed in part by said element and gearing between said memberand said transmitters for introducing corrections into said transmittersin the same ratio as said first ratio of movement.

5. In a gyroscopic compass adapted to be mounted on a dirigible craft,an A. C. transmission system including a plurality of transmitters andrepeaters yeach transmitter hav-f ing an armature and a stator, meanswhereby said compass actuates the armatures of said transmitters at apredetermined ratio of movement relative to each other, a. card carriedby each armature` a lubbers line on each stator on 'which each card isread and means also actuated in part from said compass for shifting thestators of said transmitters and the said lubber lines in the same ratiofor introducing corrections.

G. In a gyroscopic compass adapted to be mounted on a dirigible craft,an A. C. transmission systen; including a. plurality of transmitters andrepeaters each transmitter haviiw an armature and a stator, meanswhereby said compass actuates the armatures of said transmitters at apredetermined ratio of movement relative to each other, a card carriedby eacl armature, a lubbers line on cach stator on which each card isread and means including a single member, and gearing connectionsbetween said member and the stators of said transmitters for shiftingsaid stator and the attached lubber lines in the same ratio forintroducingr corrections.

7 In a. gym-compass, the combination with a follow-up element of thecompass, of a plurality of transmitters driven therefrom at differentgear ratios, a correction device for said transmitters, comprising amember rotated'in accordance with a, function of the position of saidelement, means settable in accordance with speed and latitude varyingthe drive between said member and element, and gearing of different gearratios connecting said member and each of said transmitters.

8. In a gyroscopic compass, a direction responsive element, a coarsetransmitter and a fine transmitter actuated by said element, a 360coarse compass card carried bythe coarse transmitter and a 10 Verniercard carried by the fine transmitter.

9. In a gyro compass, the combination with the follow-up element of thecompass, of a. plurality oi transmitters driven therefrom at differentgear ratios, a correction device for said transmitters, comprising amember rotated in accordance with a function of i the position of saidelement, means settable 'in accordance with speed and latitude varyingthe drive between said member and ele-v ment, separate means settable inaccordance with another function of latitude for adding an additionalcorrective movement to said member, and gearing of different gear ratiosconnecting said memberA and each of said transmitters.

l0. In a correction device for gyro ccpasses forl correcting thetransmitted reading in accordance with the expression aK eos H cos L -tbtan L,

